employing-digital-droplet-pcr-to-detect-braf-v600e-mutations-formalin

Employing Digital Droplet PCR to Detect BRAF V600E Mutations in Formalin-fixed Paraffin-embedded Reference Standard Cell Lines

ddPCR is a highly sensitive PCR method that utilizes a water-oil emulsion system. Using a droplet generator, an extracted nucleic acid sample is ...

ABION CRO

Normalization of mRNA levels using endogenous reference genes (ERGs) is critical for an accurate comparison of gene expression between different samples. Despite the popularity of traditional ERGs (tERGs) such as GAPDH and ACTB, their expression variability in different tissues or disease status has been reported. Here, we first selected candidate housekeeping genes (HKGs) using human gene expression data from different platforms including EST, SAGE, and microarray, and 13 novel ERGs (nERGs) (ARL8B, CTBP1, CUL1, DIMT1L, FBXW2, GPBP1, LUC7L2, OAZ1, PAPOLA, SPG21, TRIM27, UBQLN1, ZNF207) were further identified from these HKGs. The mean coefficient variation (CV) values of nERGs were significantly lower than those of tERGs and the expression level of most nERGs was relatively lower than high expressing tERGs in all dataset. The higher expression stability and lower expression levels of most nERGs were validated in 108 human samples including formalin-fixed paraffin-embedded (FFPE) tissues, frozen tissues and cell lines, through quantitative real-time RT-PCR (qRT-PCR). Furthermore, the optimal number of nERGs required for accurate normalization was as few as two, while four genes were required when using tERGs in FFPE tissues. Most nERGs identified in this study should be better reference genes than tERGs, based on their higher expression stability and fewer numbers needed for normalization when multiple ERGs are required.

Identification of novel reference genes using multiplatform expression data and their validation for quantitative gene expression analysis.

Isolated foot drop in acute infarction of the supplementary motor area.

Acute cerebellitis (AC) is a benign and self-limiting inflammatory disease. It typically occurs as a primary infectious or postinfectious disorder. Although AC mostly presents in early childhood, it can appear in adult. A 66-year-old man admitted to our hospital because of limb and gait ataxia. Three weeks ago, he took an influenza vaccination. There was no abnormality on brain MRI with contrast enhancement, but Technetium-99m hexamethyl propylene amine oxime-single photon emission computed tomography (HMPAO-SPECT) showed markedly cerebellar asymmetry, suggesting hypoperfusion in the right cerebellum. Influenza vaccination can cause AC in the elderly and brain HMPAO-SPECT imaging is more useful than MRI in identifying patients with AC.

An elderly case of acute cerebellitis after alleged vaccination.

A photochemical modification of melt-extruded polymeric nanofibers is described. A bioorthogonal functional group is used to decorate fibers made exclusively from commodity polymers, covalently attach fluorophores and peptides, and direct cell growth. Our process begins by using a layered coextrusion method, where poly(ε-caprolactone) (PCL) nanofibers are incorporated within a macroscopic poly(ethylene oxide) (PEO) tape through a series of die multipliers within the extrusion line. The PEO layer is then removed with a water wash to yield rectangular PCL nanofibers with controlled cross-sectional dimensions. The fibers can be subsequently modified using photochemistry to yield a "clickable" handle for performing the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction on their surface. We have attached fluorophores, which exhibit dense surface coverage when using ligand-accelerated CuAAC reaction conditions. In addition, an RGD peptide motif was coupled to the surface of the fibers. Subsequent cell-based studies have shown that the RGD peptide is biologically accessible at the surface, leading to increased cellular adhesion and spreading versus PCL control surfaces. This functionalized coextruded fiber has the advantages of modularity and scalability, opening a potentially new avenue for biomaterials fabrication.

Surface Modification of Melt Extruded Poly(ε-caprolactone) Nanofibers: Toward a New Scalable Biomaterial Scaffold.

Although partial epilepsy with structural lesions on MRI (lesional epilepsy) is less favorably responsive to antiepileptics than those without structural lesions on MRI, the response to antiepileptics in lesional epilepsy is a heterogeneous condition. There is growing evidence that the extent of epileptic network beyond the visible lesion on MRI may be related with the response to antiepileptics. The aims of this study are to clarify whether (1) the epilepsy network beyond the visible lesion on MRI, or (2) duration of lesional epilepsy on MRI are related with the response to antiepileptics or not.

Response to antiepileptic drugs in partial epilepsy with structural lesions on MRI.

A drug-eluting stent (DES) is one of the commonly used treatment techniques in percutaneous coronary intervention (PCI). Sirolimus (SRL) has been widely used for DES as a drug for suppressing neointimal hyperplasia causing restenosis. Phytoncides (PTC) are compounds released from trees and plants, and their solutions contain monoterpenoids such as α-pinene, careen, and myrceen. Some studies have reported that these components exhibit antioxidant, antimicrobial, and anti-inflammatory activities. We hypothesized that PTC may become an alternative drug to SRL for DES, exhibiting alleviated side effects as compared to SRL. A PTC-incorporated stent was compared with an SRL-incorporated stent in terms of physicochemical, pharmacokinetic, and biological properties. In in vitro studies, the effects of each drug on cells were investigated. The results showed that both drugs exhibited similar cytotoxicity, anti-inflammation, and antiproliferation effects. However, these effects resulted from different mechanisms associated with cells, as seen in the immunofluorescence result. An in vivo assay showed that the lumen area was significantly larger and the neointimal area was significantly smaller in SRL- and PTC-loaded stents compared to a drug-unloaded stent. These results suggest that phytoncide can be a feasible alternative drug to SRL for advanced DES although more studies are needed.

Comparison of phytoncide with sirolimus as a novel drug candidate for drug-eluting stent.

The objective of this study was to determine whether the adverse effects of antiepileptic-drugs could be assessed by the eye movements of epilepsy patients.

Can the adverse effects of antiepileptic drugs be detected in saccadic eye movements?

Polymeric fibers are of increasing interest to regenerative medicine, as materials made from these fibers are porous, allowing for cell infiltration, influx of nutrients, and efflux of waste products. Recently, multilayered coextrusion has emerged as a scalable and rapid fabrication method to yield microscale to submicron fibers. In this report, we describe the multilayered coextrusion of aligned poly(ε-caprolactone) (PCL) fibers, followed by a simple photochemical patterning to create surface-immobilized gradients onto the polymer fibers. PCL fibers were photochemically decorated with a linear gradient of propargyl benzophenone using a gradient photomask to control light source intensity. The pendant alkynes were then able to undergo the copper-catalyzed azide-alkyne cycloaddition reaction with an azide-modified IKVAV peptide to further functionalize the surface. Gradient-modified IKVAV fibers were evaluated for neural cell adhesion and neural differentiation, using PC-12 cells cultured onto the fibers. The aligned gradient fibers provided directional cues for neurite outgrowth and alignment of neural cells, as observed by cellular elongation, neurite differentiation, and orientation. The work presented herein describes a scalable fiber system combined with simple chemical patterning to generate aligned fibers with controlled surface gradients as cell-seeding scaffolds.

Article	Year
Identification of novel reference genes using multiplatform expression data and their validation for quantitative gene expression analysis. PloS one\| PubMed ID: 19584937	2009
Isolated foot drop in acute infarction of the supplementary motor area. Clinical neurology and neurosurgery\| PubMed ID: 23911001	2013
An elderly case of acute cerebellitis after alleged vaccination. Journal of movement disorders\| PubMed ID: 24868409	2012
Surface Modification of Melt Extruded Poly(ε-caprolactone) Nanofibers: Toward a New Scalable Biomaterial Scaffold. ACS macro letters\| PubMed ID: 24977107	2014
Response to antiepileptic drugs in partial epilepsy with structural lesions on MRI. Clinical neurology and neurosurgery\| PubMed ID: 25012014	2014
Comparison of phytoncide with sirolimus as a novel drug candidate for drug-eluting stent. Biomaterials\| PubMed ID: 25617121	2015
Can the adverse effects of antiepileptic drugs be detected in saccadic eye movements? Seizure\| PubMed ID: 25645633	2015
Coextruded, aligned, and gradient-modified poly(ε-caprolactone) fibers as platforms for neural growth. Biomacromolecules\| PubMed ID: 25715836	2015

Si Eun Kim

Biography

JoVE Journal Publications

Other Publications